<!DOCTYPE html>
<html lang="en">
<head>
  <meta charset="UTF-8">
  <meta http-equiv="X-UA-Compatible" content="IE=edge">
  <meta name="viewport" content="width=device-width, initial-scale=1.0">
  <title>斐波拉契数列</title>
</head>
<body>
  <script>
    /*
     1 1 2 3 5 8 13 24 34.。。。。
    */
    //1. 找规律
    //2. 找出口

    // fb(n) = fb(n-1) + fb(n-2)
    function fb(n) {
      if (n === 2 || n === 1) {
        return 1
      }
      return fb(n-1) + fb(n-2)
    }
    fb(12)
    console.log(fb(6))
  </script>
</body>
</html>